Hated Veggies As A Kid? These Are The Scientific Reasons Why

Lookin' at you, broccoli.

If you think back on your childhood, there are a few memories that will stand out -- the day you learned how to ride your bike (without training wheels or falling over), your first day of school, going away on holidays, making best friends forever at school...

And, of course, all the times your parents tried to feed you disgusting soggy brussel sprouts and broccoli. And remember your first sip of beer, wine or coffee? Blegh.

Chances are, now that you're an adult and you can do your own washing (hopefully), you probably love beer, wine, coffee. You also don't completely hate broccoli anymore.

A popular theory for this is that, over time, our taste buds change. While it's nice to think that our baby taste buds grow to become smart and change to appreciate adult things, this isn't necessarily true.

According to Russell Keast -- a professor in sensory and food science and the director of the Centre for Advanced Sensory Science at Deakin University -- our aversion to vegetables and 'adult' drinks has to do with fascinating evolutionary reasons.

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"A lot of the work we've done in terms of how people develop liking to foods has been based around caffeine and the role it has," Keast told The Huffington Post Australia.

"Caffeine is a bitter compound and it's naturally found in coffee, tea and chocolate. It's also an additive to certain cola beverages. That's interesting because bitterness by itself is one of these warning signals."

That is, through our species' evolution, we have learned that it's vitally important not to consume something that's potentially dangerous (bitter).

It was often that plant foods contained compounds that may be harmful, so some more bitter foods, like brussels sprouts or olives, triggered natural protective responses long ingrained in our DNA.

"If you go outside and pick up a leaf, put it in your mouth and chew it, it's invariably going to be bitter. That's because we've got a system which says it may be dangerous," Keast explained.

"The system is incredibly robust in that it identifies tens of thousands of compounds, and all it's suggesting is the bitter product (via aversiveness) may contain something that causes harm."

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No wonder kids hate vegetables when they're served like this.

For our species' survival, taste (especially bitterness and sourness) has been critical. Yep, we are smart.

It's no surprise then to learn that your favourite veggies, especially broccoli and brussel sprouts, contain this bitter compound.

"In fact, it was often that plant foods contained compounds that may be harmful, so some more bitter foods, like brussel sprouts or olives, triggered natural protective responses long ingrained in our DNA," Keast said.

"Sensitivity [to bitter compounds] is a little bit higher when we're young. Within this spectrum, there's also huge amount of variation between people."

If you still really hate (or can't stomach) broccoli as an adult, and you've honest to god tried many times, you may be a 'super taster'.

"If somebody is experiencing high levels of bitterness, let's say, to broccoli, doing things like repeated exposure of that food isn't necessarily going to teach liking of that food," Keast told HuffPost Australia.

"There's a lot of variation in how we experience these foods. Somebody may have a great aversion to broccoli because they've got the bitter taste receptors that are responsive to a specific compound in broccoli. Whereas other people don't have that receptor and, therefore, don't experience the bitterness from broccoli."

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We're also not that interested in veggies because they grow in abundance.

But there's another evolutionary reason why children (and some adults) dislike vegetables.

"With vegetables specifically, we have had no reason to develop an overt liking response to them," Keast explained. "Plants were generally plentiful so we didn't need an incentive to seek them out.

"Now we have supermarkets with foods developed to our liking, so we don't need these primal responses, but they are ingrained in our DNA and it will take thousands of years for them to evolve out."

So, why is it when we age that, all of a sudden, we like broccoli? The answer is not that our taste buds change, but we just learn to like it.

"We build up a taste for things through gradual exposure,' Keast said.

If the nutrients provide energy, perhaps other positive effects in your body, your liking system will remember, the next time you eat the food you may start to enjoy it.

"There's a number of things we don't like when we first experience them, but a lot of learning comes into it. That's the critical thing when it comes to developing taste.

"A lot of the turn off when you're younger can be because of unusual flavours, bitterness or texture related. There's a whole variety of things. Bitter is obviously one of the key components that will turn people off certain foods."

But vegetables are safe, which is why it's so important for kids and adult veggie haters to try them again, and again.

"This gives the nutrients in the food a chance to influence your liking system -- if the nutrients provide energy, perhaps other positive effects in your body, your liking system will remember, the next time you eat the food you may start to enjoy it," Keast said.

"There can also be an opposite effect. If you have a night of binge drinking whiskey and become sick, the mere thought of whiskey the next day might be enough to turn your stomach. That's your body protecting you from something that might make you unwell."

Chris Cross
We overlook the bitterness of alcohol and coffee because they make us feel good.

Interestingly, it's easier to enjoy particularly bitter drinks like alcohol and coffee because we subconsciously override the aversion to the bitterness to experience the positive feelings we get from, you know, becoming drunk or caffeinated.

"With bitter drinks such as coffee or beer, we will drink them because they give us positive post-digestive consequences," Keast explained.

"Coffee gives us caffeine which is mildly addictive and also makes us feel more alert. It's the same with beer -- alcohol is addictive and can make us feel good."

When it comes to trying vegetables again, Keast has a few simple tips to make them more delicious.

"When you're an adult you know what you like. The ability to cook, whether it's a cooking method of different additions to cooking, may help you overcome an aversion. If you don't like broccoli, try not overcooking (or maybe overcooking) them as a way of changing things up," Keast said.

"Also, pairing broccoli with something you like may help you overcome the aversion."

Basically, don't cook veggies like your parents used to make them. Try those brussels sprouts again, perhaps roasted with olive oil, salt and pepper. You and the kids just might like them.